This invention relates to mobile cranes of the type known as "rough terrain" cranes in which the operator's cab is mounted on a crane superstructure rotatably carried on a vehicle chassis.
Prior to this rough terrain cranes had a control cab mounted on the vehicle chassis, giving the driver good control and highway visibility in moving the crane from place to place but rendering operation of the crane difficult and often hazardous as the operator often has to look over his shoulder away from the crane controls to see as much of the working area as is not obscured by the crane superstructure.
Mobile cranes of the type referred to have been proposed having two separate control cabs, one mounted on the chassis with vehicle controls only for use in moving the crane and the crane control cab having sufficient duplicated controls for low-speed manoeuvering of the crane in use. Such cranes necessarily have a long wheelbase for permitting rotation of the superstructure with clearance from the chassis control cab.
It has also been proposed to provide two control cabs, in "back to back" formation centrally of a chassis with the crane controls in the cab facing the crane boom and the vehicle control cab facing the opposite direction with forward vision over the front part of the chassis for highway driving. A long wheelbase is required unless the chassis deck level can conveniently be raised above the engine in order that the vehicle control cab may swing over the engine area.